I am unclear about whether my set up is the same or different from others posting on this discussion, in Mail, Contacts, Calendars. What i see when i go to Calendars, Default Calendar, is two headings. One says iCloud, the other says my email address which is my Gmail address, which is my Apple ID. I think that my iCloud address is considered (in the iOS system) to be a sort of Apple ID as well, it's a me.com email. but i don't use it for anything, email or anything else, except logging into iCloud.
Anyway, again, i have two headings under Default Calendars, iCloud and my apple ID gmail email address. Does this make any sense to anyone? Does anyone else have headings, one or more, in Default Calendars? Neither of these headings are selectable as 'default calendar.' They are just (apparently) category headings for two types of default calendars. Under the iCloud heading are 9 selectable calendars, including Health, Finance, Family, Pets, etc. Any one of these can be selected to be the default calendar. Or, under the second heading, which is titled my Apple ID gmail address, there is one selectable calendar. It has my user name, which is my actual name--that is what i can select, if i want to choose a non-iCloud calendar as default calendar. Does anyone else have anything that looks like this? If not, what do others have on the Default Calendar page? What does it look like?
I have to some extent located the problem in my system that causes GMT to be included in my new calendar entries. I have always been using my Apple ID gmail address as my default calendar, at least as far as i know. I never had an issue that drew my attention to this until i got the iPhone 6 on 11/25, so i never knew there was such a thing as a default calendar until i encountered this GMT problem and two other apparently related calendar problem, a few weeks after getting my new iPhone. i did not have these problems immediately, they started after a few weeks, independent of any iOS change. Before that i had a 4s running iOS 5. i just restored from back up and so, i assume my settings were the same.
I don't remember now what drew my attention the default calendar setting in my effort to trouble shoot this (and the other two) Calendar problem/s, but i discovered that as long as my default calendar is the Apple ID Gmail address user name one, i will always get GMT info on my new calendar entries. On the other hand, if i change my default calendar to any of the iCloud calendars, i get no GMT info on my entries, just like before the problem started, so the problem is apparently solved simply by changing my default calendar to any one of the iCloud calendars. I created a new iCloud calendar called All Cloud and that is my default calendar, but it could be Pets or Health or whatever, just so it's an iCloud calendar.
The other two apparently related problems i was having that were also solved by this change were, one, all my entries would have a 30 minute alert, despite no alert in settings, and no alert selected when creating the event, and two, the worst problem, my calendar entries weren't syncing to iCloud, nor, therefore to iCal. They were only on my phone. Changing to an iCloud default calendar eliminated these three problems. Now, my calendar is functioning correctly as it did before.
I would like to know if others who have had this GMT problem have an iCloud calendar as their default calendar. i don't know, at this point, whether there are any negative consequences from no longer using my long-time Gmail address user name which is my main Apple ID, as my default calendar.